I'm a principal software engineer. I've spent my career building software that's reliable, clear, and maintainable, and helping teams grow along the way. My work is in Go and Python, though these days I mostly direct AI coding agents and spend my own time on design, review, and the limits I set for those agents. 🤖
For most of the last decade that has meant developer experience: test engineering, CI/CD, delivery metrics, feature flags, and lately sandboxes for coding agents. I did that work at Mozilla for seven years, then at Aleph Alpha, and most recently at Manifold Security.
I was lead developer of cookiecutter and a pytest core team member. Some of that work is under my former name, Raphael Pierzina.
- opportunities: a local-first CLI in Go and PostgreSQL for keeping track of job opportunities and applications
- nono-packs: hardened nono profiles for coding agents, starting with a Claude Code pack that blocks macOS keychain access, sandboxes the OAuth login, and tightens filesystem and environment access
- skills: Addy Osmani's skills for AI coding agents, reworked for backend and tooling work
I'm open to new opportunities. The best way to reach me is by email, and you can find more of my writing and talks at raphael.codes. 💬